Pahlavi Texts, Part IV (SBE37), E.W. West, tr. [1892], at sacred-texts.com
The whole of this Nask (as described in Dk. VIII, Chap. XLIV) is still extant, and is considered by the writers of the Persian Rivâyats to be a complete work. Its fragmentary character, which is obvious enough to European scholars, must, therefore, be
attributed, in all probability, to losses it sustained before the revival of Mazda-worship by the Sasanian dynasty. It is remarkable that the compiler of the account in the Dinkard makes no allusion to the twelfth fargard of the Vendîdâd, which is also omitted in all old MSS. of the Vendîdâd with Pahlavi that have been examined, although the copyists appear to have been aware of the existence of a twelfth fargard.
481:3 The extent of this Nask appears to be the same now as it was in Sasanian times, and may be estimated at about 23,000 Avesta and 48,000 Pahlavi words. The moderately long account of it in Dk. VIII, contains 1,272 Pahlavi words.